· web viewobjectives make predictions and compare the results for a participatory simulation...

What Causes Competition Between Individuals in an Ecosystem?

Time2 class periods

LevelCan be scaled to work with middle school through high school students

Purpose and Overview The purpose of this activity is for students to describe how consumer/producer interactions for limited resources necessary for survival leads tot the emergence of a competition for those resources, even when there is no intentional effort being made by individuals to outcompete each other.

Learning Objectives

Make predictions and compare the results for a participatory simulation of a simple consumer/producer ecosystem.

Analyze population histogram graphs from a simulation to identify the range of the graph and where most individuals are concentrated.

Identify and critique the modeling assumptions used in a computer model of a simple consumer/producer ecosystem.

Compare the variations in the local surroundings between two individuals in the same ecosystem.

Calculate how the amount of grass and amount of bugs would affect the average amount of grass available per bug, and likewise how changes in this average food availability would affect the death rate and birth rates in the bug population.

Describe how local variations of resources necessary for survival contributes to differences in the level of success different individuals have in acquiring those resources.

The behavior of a physical (or computational) model cannot ever be expected to represent the full-scale phenomenon with complete accuracy, not even in the limited set of characteristics being studied... 11B/H5** (SFAA)

In all environments, organisms with similar needs may compete with one another for limited resources, including food, space, water, air, and shelter. 5D/M1a*

A system usually has some properties that are different from those of its parts, but appear because of the interaction of those parts. 11A/H1 (Preliminary text from Benchmarks)

This work is supported by the National Science Foundation under NSF grant CNS-1138461. However, any opinions, findings, conclusions, and/or recommendations are those of the investigators and do not necessarily reflect the views of the Foundation.

Copyright © 2012 Northwestern University CT-STEM

Computational Thinking in STEM Skills:-Analyzing and visualizing data-Understanding the relationships within a system.

Next Generation Science Standards:

Analyzing and Interpreting Data:-Use tools and models to generate, gather and analyze data

Patterns:-Different patterns are observed at each scale of a system and can provide evidence for causality-Classifications used at one scale may need revision when information from smaller or larger scales is introduced.

Developing and Using Models:-Use / construct models to predict / explain relationships between systems and their components

BackgroundNew Scientific Principles

All ecosystems have a limited amount of resources needed for survival. Some individuals will be more successful than others at consuming the resources in

an ecosystem, simply because the distribution of resources around each individual vary.

Teaching NotesIn this activity, students are introduced to a participatory computer simulation

where each student takes the role of an individual consumer in the predator prey ecosystem. Students make predictions about various model runs and compare their predictions to the outcomes they observe. In two explorations they control the direction



of movement of a bug, trying to gather as much food (grass) as possible in a variety of conditions. In one exploration they observe the outcome when many bugs move randomly and blindly around an ecosystem consuming food without any intentional control.

Students recreate a physical representation of a histogram graph (of energy levels of bugs) from NetLogo and analyze characteristics of the population in the graph.

In the summary class discussion, students describe what they discovered: Competition is an emergent outcome that results from 1) limited resources necessary for survival, 2) and unequal distribution of those resources throughout the ecosystem, 3) and intentional actions on part of the individuals or from the unintentional interactions that always are occurring between each individual and their environment.

In the homework students address the difference between intentional and unintentional competition further. They critique the modeling assumptions used in the computer simulation. They describe the variation in local resource availability for individuals in the computer model. They calculate how changes in the amount of grass or amount of bugs in would change the average amount of grass per bug in the ecosystem and they identify that ecosystems with lower average grass per bug would have higher levels of competition than those with higher average amounts of grass per bug.

Materials and Tools

Per Student 1 computer per student with HubNet and NetLogo installed. One post-it note

For Teacher 1 computer with NetLogo installed along with a copy of the Bug Hunters

Competition.nlogo model file to host the multiplayer version of the game that all the students will join over the network.

1 computer and projector or large display screen for the teacher to display the computer model.

1 piece of butcher paper or poster paper or space on the wall for students to stick the post it notes on.



AssessmentThe class discussion and homework assignment serve as assessments.

AcknowledgementsThis lesson and all Netlogo models were developed by the Northwestern University Center for Connected Learning. Please see http://ccl.northwestern.edu/simevolution/beagle.shtml for the full BEAGLE curriculum from which this lesson is taken.

Teacher instructions for using Hubnet and the Netlogo models are on the following page.



http://ccl.northwestern.edu/simevolution/beagle.shtml

· web viewobjectives make predictions and compare the results for a participatory simulation...

Documents